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skbio.diversity.alpha.strong#

skbio.diversity.alpha.strong(counts)[source]#

Calculate Strong’s dominance index.

Strong’s dominance index (\(D_w\)) is defined as

\[D_w = max_i[(\frac{b_i}{N})-\frac{i}{S}]\]

where \(b_i\) is the sequential cumulative totaling of the \(i^{\text{th}}\) taxon abundance values ranked from largest to smallest, \(N\) is the total number of individuals in the sample, and \(S\) is the number of taxa in the sample. The expression in brackets is computed for all taxa, and \(max_i\) denotes the maximum value in brackets for any taxa.

Parameters:
counts1-D array_like, int

Vector of counts.

Returns:
double

Strong’s dominance index.

Notes

Strong’s dominance index is defined in [1].

References

[1]

Strong, W. L., 2002 Assessing species abundance unevenness within and between plant communities. Community Ecology, 3, 237-246.